Need tips for light bar print not sticking
I have a freshly assembled MK3/S with textured steel print plate.
Objects like the Pi camera case adhere well - and print perfectly.
I am having trouble with the MK3/S led light bar. This is two skinny, long rails.
It is set for PLA, 210 degrees (seems cold).
Same rail lifts from the bed every time at the end of the rail, about level 5.
Tried a half dozens times. Wiped the bed down with IPA and even gave it a Dawn soak. No improvement.
Any suggestions? About to break this print down and print one rail at a time.
RE: Need tips for light bar print not sticking
Corollary question: What can I do with PC sheets to increase adhesion with PLA?
Windex? Glue stick? Hair spray? Increased bed temp? Reduced bed temp after first layer? Incantations?
Printing this light bar support one rail at a time is working - but one end has lifted 1/16" by the time it is 1" high.
RE: Need tips for light bar print not sticking
Corollary question: What can I do with PC sheets to increase adhesion with PLA?
Windex? Glue stick? Hair spray? Increased bed temp? Reduced bed temp after first layer? Incantations?
Printing this light bar support one rail at a time is working - but one end has lifted 1/16" by the time it is 1" high.
Are you using the PC or PEI sheet? They are VERY different. According to Prusa the PC sheets should never have soap/Dawn, water, or Windex used on them. Please see this link: https://blog.prusaprinters.org/how-to-print-on-a-powder-coated-sheet/
If it's PEI try this website: http://projects.ttlexceeded.com/3dprinting_bed_cleaning.html
Try those things out and see if it helps. If you are using the PEI sheet there is a different page to assist.
RAH
I am the inveterate tinkerer. I can tink up most anything.
RE: Need tips for light bar print not sticking
As mentioned this is a PC sheet. I started off using only 99% Isopropyl.
Since the problem did not improve, I did use the scrub with Dawn treatment, heat drying immediately after.
The question was - and is - what can I do to an IPA cleaned PC sheet to increase adhesion?
Live Z tuning is as close as I can get it. That leaves bed and extruder temperatures. Those are the standard 60/210 for all layers.
RE: Need tips for light bar print not sticking
From what I've read on the forum, soap and water is the go-to solution to get PLA to stick on PEI or Ultem (PC) sheets. Alcohol will work if you use enough; but most of us don't have industrial alcohol baths to soak and degrease the sheets properly.
The advice is clean thoroughly once with soap and water: then use the don't touch rule. Use gloves when handling or cleaning the sheet with alcohol because alcohol moves oils from your fingers to the sheet just as easily as it moves oil around the sheet.
My pet theory based on PEI sheets: alcohol will leave a micro thin sheen of oil ... one that is very effective at preventing PLA adhesion. Same with acetone. So if you use these to clean, be prepared to use a lot of it to get a good rinse. A CC won't do much.
RE: Need tips for light bar print not sticking
I am actually making progress...
Most important change seems to be to increase the bed temperature to 70. I would not do that for a PEI sheet...
That single change lets me print tall and skinny objects like the linear bearing lubricator and cap.
That plus a brim let me print the light bar hex studs. No idea why they were a problem.
All I have left on the light bar is the other long shinny rail. I will try that with a brim.
Note: I think all of this is specific to the powder coated textured sheet and PLA. The PEI sheet would have worked fine.
I have a spool of PETG coming tomorrow - I expect it to do fine with the PC. Lower coefficient of expansion and all.
And I fully intend on using water and Dawn in the future as needed. Maybe monthly.
RE: Need tips for light bar print not sticking
I have a terrible time telling what calibration images should look like. Could I get a comment on these? This is the 60 mm circle, two layers. Measured thickness at center is .043 mm. The rim on one side is rough and .073 mm. Could be why I am catching an edge.
RE: Need tips for light bar print not sticking
I don't use the textured sheets so I don't have any personal experience with them. But good examples come on the printer: and in all those cases there aren't any visible extrusion lines in the texture. I'm not sure what the Galaxy Black should look like, the Mystic Brown I used the sparkly filler would flow and make odd patterns and I expect the same of the black filler, so it might be that effect I am seeing. Your prints look pretty close to ideal, but my impression is you could go a bit thinner, a bit more negative on Live-Z. Not much, just enough to fully fill the texture - probably no more than another -25 microns.
RE: Need tips for light bar print not sticking
My current setting is -1.090, not that that means much. It does show I spent a lot of time going thinner...
Any idea why one edge would be rough and raised? Seems like second layer is dragging at start.
And thanks for your input! You are one of the ones I follow here. And Bob, and Joan...
RE: Need tips for light bar print not sticking
A dirty bed will cause the PLA to lift ... have a look at this example. Bed looks spotless but since I had used alcohol on it I actually put down a nice invisible layer of oils ... and note how some of the edges are curling back ... and the second layer comes along and lifts most anything it touches.
RE: Need tips for light bar print not sticking
ps: Don't be afraid to raise the bed temp to help adhesion for warp prone parts: I've gone as high as 75c with PLA on my PEI sheet.
RE: Need tips for light bar print not sticking
ps: Don't be afraid to raise the bed temp to help adhesion for warp prone parts: I've gone as high as 75c with PLA on my PEI sheet.
Tim,
Does raising the bed temp run the risk of creating elephant foot? Possibly the reason for the thinner edge when running 2 layers onto the plate?
Curious minds...
RAH
I am the inveterate tinkerer. I can tink up most anything.
RE: Need tips for light bar print not sticking
ps: Don't be afraid to raise the bed temp to help adhesion for warp prone parts: I've gone as high as 75c with PLA on my PEI sheet.
Tim,
Does raising the bed temp run the risk of creating elephant foot? Possibly the reason for the thinner edge when running 2 layers onto the plate?
Curious minds...
RAH
Sure, but if the part is lifting and causing problems, does it matter if it lets the print finish? And, when I do this, I generally leave the bed at 60 until several layers are down, so the foot issue is avoided.
But still trying to guess what "rough edges means" ... difficult without a picture. I'm guessing some edges are curling due to contamination. But operative word there is "guessing." The old "not enough information: problem. I should probably avoid suggesting anything until the cause is obvious. Let others do the guessing.
RE: Need tips for light bar print not sticking
Tim,
As we are all in the learning phase of the process at varying levels it does really help to get on a level set. I have the same wish you do, namely that we would get all of the facts and some decent pictures to display the issues we respond to.
I am working on printing many of the same part and get varying first 2 layer issues which lead me to believe that preparation is the KEY element to all 3D printing issues, (once the 3D printer is dialed in to make decent prints). I do understand lifting edges and incomplete perimeters all too well. Most of them seem to be bad surface prep. I have found methods to reduce that from happening but I am nowhere near perfect.
One problem that I see, causing failed prints, is "bird droppings" in the first 2 layers but rarely afterwards. Once cleaned up, I could raise the bed temp to reseat the pull off from the bed. I have found that most times just using a diagonal cutter and letting the existing bed temp do the rest I get a decent print. I may try to raise the bed temp next time. YMMV.
RAH
I am the inveterate tinkerer. I can tink up most anything.
RE: Need tips for light bar print not sticking
"Gnats" -- the small plastic fragments left due to too hot a nozzle during mesh leveling -- are 100% avoidable. And any loose fragments that happen during layer 1 and 2 are assembly issues (leaky nozzle threads, usually); or drag and drop from adhesion problems (at least in my experience), also 100% avoidable. But then, the fact is these things do have other causes, however rare they may be. So the way I phrase things gets me in trouble. Sort of like using diagonal cutters -- more often than not I'll rip the part off the bed because I have to duck the extruder just as I get positioned to clip. Nothing is truly certain.
RE: Need tips for light bar print not sticking
"Duck the extruder" - I have found using the Pause Print option to work wonderfully.
The extruder moves up and away - I do my rescue work - and Resume Print picks up right where it left off.
RE: Need tips for light bar print not sticking
Isn't the goal to NOT have to rescue the print in the first place?
RE: Need tips for light bar print not sticking
Isn't the goal to NOT have to rescue the print in the first place?
Tim,
Yes. True. Thank you again for the heat bed/nozzle heat up mods to Prusa Slicer. I have a part ready to test as soon as the one I am printing is done, (in about 1.5 hours). 😀
RAH
I am the inveterate tinkerer. I can tink up most anything.
RE: Need tips for light bar print not sticking
To resolve this problem you have to:-
- Increase the heat of the printing bed by doing this once your printing bed is heated the filament will be able to stick better with the printing bed.
- Also, you need to check your printing bed should have oil. You can clean your printing bed with a cloth to remove anything sticking to the bed.
- Your printing bed should be flat and calibrated
RE: Need tips for light bar print not sticking
Isn't the goal to NOT have to rescue the print in the first place?
Tim,
Yes. True. Thank you again for the heat bed/nozzle heat up mods to Prusa Slicer. I have a part ready to test as soon as the one I am printing is done, (in about 1.5 hours). 😀
RAH
Part printing now. I did have to rescue it a bit. 🙁 Looking into the other possibilities. Extruder disassembly is likely after a few more prints. I might even get the filament out sensor to work. 😉
RAH
I am the inveterate tinkerer. I can tink up most anything.